cracks in frame? (Full Version)

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cracks in frame?

  

thrasher572 -> cracks in frame? (1/7/2008 10:24:54 AM)

I have looked at 3 hurricanes recently and all had a crack on the frame in the same place.  The crack is on the underside of the main frame rail just in front of the rear motor mount. Any ideas?  What do you think causes it?   I have stripped one bike down and had the frame welded.

  
michigan_313 -> RE: cracks in frame? (1/7/2008 11:46:14 AM)

picture?

is it a cracked weld or crack in the frame spar?

did you see any dents in the frame near the crack?

what side of the frame are you seeing this at?

are all frames owned by same entity?

i'll go look at both of my frames tonight.

michigan_313 -> RE: cracks in frame? (1/7/2008 7:01:27 PM)

i looked on both my frames and i don't see any cracks assuming i'm looking in the same place you are describing. a picture would help.

thrasher572 -> RE: cracks in frame? (1/7/2008 10:24:47 PM)

All the bikes were from different owners... the crack is forming on the left side main spar just in front of the guide for the top, rear engine mount. The crack itself extends around the bottom of the spar and it is on the larger of the two frame sections...behind the weld. It looks like a stress crack. There is no obvious damage anywhere else on the frame. The odd part is that the crack has not appeared on the copy I bought new. I aquired two of the bikes very cheap because of the frame damage... I will take a picture and post it so you can see exactly where the crack shows up.
 

thrasher572 -> RE: cracks in frame? (1/7/2008 10:56:42 PM)

this is the repaired frame ... Iwill have to pull the plastic to show the other frame that still has the crack

tripicana -> RE: cracks in frame? (1/7/2008 11:19:58 PM)

i just looked at my bikes.  one of my two '87 frames is cracking in that same spot.  its just starting around the outside frame, next to the weld, for the rear engine mount.

thrasher572 -> RE: cracks in frame? (1/8/2008 6:37:50 AM)

I have a theory about why they crack and why my original owner bike has not... we all know the high frequency vibration that is transmitted through the bike around 5500 rpm... That engine speed tranlates to 60mph of 100kmh in top gear with stock gearing. My bike has seen redline almost every shift for 20+ years and has not spent a lot of time in that rpm range and the frame is fine... I believe the frames that are cracking are on bikes that have been ridden "gently " and at or near the speed limit and in the high frequency buzz rpm too much. It is just a theory....

thrasher572 -> RE: cracks in frame? (1/8/2008 10:57:51 AM)

here is the other frame with the crack visible.

thrasher572 -> RE: cracks in frame? (1/8/2008 10:59:50 AM)

second attempt

thrasher572 -> RE: cracks in frame? (1/8/2008 12:42:28 PM)

Tripicana, do you know the history of the bike with the crack? Has it been rode hard ... wheelied lots? Babied?  Crashed?  It would be interesting to know how many other hurricanes have the crack...

tripicana -> RE: cracks in frame? (1/8/2008 3:24:40 PM)

i dont know the history of either bikes. except they were both at around 20,000 miles.  ill probably get the crack welded because its on the frame that i have a title for.  i wonder if there is anything honda could do if we could find enough cracks on other bikes. 

telgren -> RE: cracks in frame? (1/8/2008 3:57:06 PM)

quote:

ORIGINAL: tripicana

i dont know the history of either bikes. except they were both at around 20,000 miles.  ill probably get the crack welded because its on the frame that i have a title for.  i wonder if there is anything honda could do if we could find enough cracks on other bikes. 


We have to take into account the bikes are all 20 years old, the frames are probably realisticly more along the lines of 22 years old.  The frames were made with an older heavier steel, which was probably coated originally but probably has worn off at certain points.  Remember that todays steel is tempered so that its not as prone to cracking and improvements in welding makes welds stronger than the steel its bonding, as the frames of 87 are certainly strong (lets face it there is more steel in an 87-88 frame than in todays vokswagens) they will crack.

I urge everyone who is having their frames welded, its done by a professional machine shop, and not some yahoo with a 110 volt wire feed welder.  I cant remember what exactly the frame composition is, but if welded improperly they can cause more damage than good.

The source of the cracking is probably more or less from riding.  the bikes do take a beating if it be normal nice soft riding, or someone doing stunts.  Shocks take 99% of the effects but some is bound to push through...  we all know that the seals on the forks go out with regularity, and cause ill effects.

thrasher572 -> RE: cracks in frame? (1/8/2008 4:12:15 PM)

I seriously doubt that honda or any other manufacturer would do anything about a product that they sold 20 years ago, particularly a high performance product that many of us have had the time of our lives tearing up the roads on.  If you are shopping for a used one it is buyer beware... and now you know one more thing to check before money changes hands.

  

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